And yet the long saloons of the palace with their rich decoration had need of light, which they could only obtain through the doorways and the openings left in the roof. When this was of wood the matter was simple enough, as our diagram (Fig. 60) shows. Botta noticed, during his journey to his post, another arrangement, of which, he thinks, the Assyrians may very well have made use. [Illustration: FIG. 61.--Armenian "Lantern;" from Botta.] "The houses of the Armenian peasantry," he says, "are sunk into the ground, so that their walls stand up but little above the level of the soil. They are lighted by an opening that serves at once for window and chimney, and is placed, as a rule, in the centre of the roof. The timber frame of this opening is often ingeniously arranged (Fig. 61). Four thick beams, but very roughly squared, intersect each other in the middle of the house. Across their angles slighter joists are placed, and this operation is repeated till a small dome, open at the top, for the entrance of light and the escape of smoke, has been erected."[225] [Illustration: FIGS. 62-65.--Terra-cotta cylinders in elevation, section and plan; from Place.] In the case of vaults how are we to suppose that the rooms were lighted? We can hardly imagine that rectangular openings were left in the crown of the arch, such a contrivance would have admitted very little light, while it would have seriously compromised the safety of the structure. According to M. Place the desired result was obtained in more skilful fashion. In several rooms he found terra-cotta cylinders similar to those figured below. These objects, of which he gives a careful description, were about thirteen and a half inches in diameter and ten inches in height. We may refer our readers to the pages of M. Place for a detailed account of the observations by which he was led to conclude that these cylinders were not stored, as if in a warehouse, in the rooms where they were afterwards found, but that they formed an integral part of the roof and shared its ruin. We may say that the evidence he brings forward seems to fairly justify his hypothesis.